<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
    <body>
        <!-- 2.准备容器 -->
        <div id="hello">
            {{ msg }}
        </div>
    </body>
    <!-- 1. 引入vue3源代码-->
    <script src="https://unpkg.com/vue@3/dist/vue.global.js"></script>
    <script>
        // 3.创建Vue3应用并引入数据
        Vue.createApp({ 
            // Vue3的入口函数
            setup() {
                let msg = "hello world"
                return {
                    msg
                }
            }
        }).mount("#hello")//返回值调用mount指定容器
    </script>
</html>